FACE™ c-Src

in-cell Western analysis for phospho c-Src (Y418)

Fast Activated Cell-based ELISA (FACE™) Kits provide a simple, sensitive method for detecting protein phosphorylation directly in the cell, without making extracts or performing electrophoresis and membrane blotting. These 96-well, high-throughput assays are available in both colorimetric and chemiluminescent formats for over 20 different targets (see list at right). For complete details, click the FACE™ Method tab below.

FACE c-Src Kits provide 96 rxns each of 2 antibodies that enable you to monitor and compare the levels of both phosphorylated and total c-Src. The phospho-c-Src antibody recognizes c-Src when phosphorylated at Tyr418, and also recognizes Fyn and c-Yes; total-c-Src antibody recognizes c-Src regardless of the phosphorylation state. Click the c-Src Info tab below for data and more information.

Figure 1: Measurement of phosphorylated and total c-Src.

A-431 cells were cultured in 96-well plates and serum-starved for 16 hours. Cells were then treated with 100 ng/ml EGF for 20 minutes and fixed. Total and phospho c-Src were each assayed in triplicate using the phospho and total c-Src antibodies included in the FACE c-Src Kit. Data was plotted after correction for cell number (performed through use of Crystal Violet).

Antibody Specificities

The phospho-c-Src antibody is specific for phosphorylated c-Src and was raised against a synthetic phospho-peptide corresponding to residues surrounding Tyr418 of human c-Src. This antibody recognizes c-Src when phosphorylated at this site and also recognizes Fyn and c-Yes. The total-c-Src antibody recognizes c-Src proteins regardless of the phosphorylation state.

c-Src Overview

c-Src (proto-oncogene tyrosine-protein kinase Src) is a 60 kDa tyrosine protein kinase that contains both SH2 and SH3 domains. c-Src is a lipid-modified signaling molecule (myristoylated) involved in cell-cell interactions, cell migration and proliferation through the phosphorylation of many substrates. c-Src is expressed at high levels in differentiated cells including neurons, platelets and macrophages, and can be activated by phospholipase D, insulin-like growth factor receptor, EGF-receptor, fibroblast growth factor receptor and prolactin receptor binding. c-Src can be phosphorylated on multiple sites to interact with polyoma virus middle T antigen, PYK2, HSP72 and caveolin, and efficient study methods are in high demand.

The FACE™ Method

In FACE, cells are cultured in 96-well plates and stimulated to induce the pathway of interest. Following stimulation, the cells are fixed rapidly, which preserves activation-specific protein modifications. Each well is then incubated with a primary antibody specific for the activated protein of interest. Subsequent incubation with secondary HRP-conjugated antibody and developing solution provides a colorimetric or chemiluminescent readout that is quantitative and reproducible (Figure 1). The number of cells in each well can be normalized easily with the provided Crystal Violet solution. FACE Kits also contain primary antibody specific for the native inactive protein, so you can monitor both native and activated protein levels in the same experiment. FACE eliminates cellular extractions, radioactive kinase assays, time-consuming Westerns and inefficient epitope interactions that occur on membranes. FACE is a highly sensitive high-throughput assay designed for detecting activated proteins within mammalian cells.

Figure 1: Flow chart of the FACE process.

Flow chart of the FACE in cell Western method that uses a cell based ELISA to measure the levels of the native and phospho forms of signaling proteins and kinases that are activated by phosphorylation.